The Experts below are selected from a list of 252 Experts worldwide ranked by ideXlab platform

A T De Almeida - One of the best experts on this subject based on the ideXlab platform.

  • switched Thermal Anemometer
    Instrumentation and Measurement Technology Conference, 2008
    Co-Authors: Lino Marques, G Tomaszewski, A T De Almeida
    Abstract:

    A new experimental circuit arrangement for a Thermal Anemometer using a microcontroller as a control unit is described. The device uses a boost-configured self-heated thermistor as a flow detection sensor. Two different operating modes are presented: a sigma-delta constant temperature operating mode and a transient-temperature based operating mode. Both modes are compared and experimental results showing the performance in both cases are presented.

  • ThermalSkin: A Distributed Sensor for Anemotaxis Robot Navigation
    2006 5th IEEE Conference on Sensors, 2006
    Co-Authors: Lino Marques, A T De Almeida
    Abstract:

    This paper presents a biomimetic Thermal Anemometer - called ThermalSkin - to measure airflow intensity and direction around solid structures. The ThermalSkin airflow sensing system is based on the information provided by a network of small Thermal Anemometers (Thermal "scales") placed around an airflow deflecting structure. This approach is inspired by the wet finger approach used by old men to estimate the direction of the wind. In this method, the coldest part of the finger (the part with higher Thermal dissipation rate) points in the upwind direction. Although the system has been developed for robotics, its principle is general allowing a straight adaptation for most applications requiring the measurement of fluid intensity and direction around a solid body. The scale elements are smart Thermal Anemometers able to measure the wind intensity near their surfaces. Each scale is composed by a constant temperature self-heated thermistor, the respective signal conditioning circuit and a Microchip PIC microcontroller that interfaces with a LIN-based network. The simple (3-wire bus) and smart structure of the system provides a framework easy to set-up and calibrate. A central controller gathers data from each sensing element and estimates the local airflow vector.

  • IROS - Environmental monitoring with mobile robots
    2005 IEEE RSJ International Conference on Intelligent Robots and Systems, 2005
    Co-Authors: Lino Marques, Aníbal Alberto Sá Martins, A T De Almeida
    Abstract:

    This paper describes an architecture for estimating environmental odor maps and presents experimental results obtained using that architecture with five mobile robots inside a large laboratory with two odor sources and forced ventilation. The mobile sensing agents employed in the experiments have self localization capabilities and carry an electronic nose and a Thermal Anemometer. The proposed architecture allows integrating sparse olfaction data gathered by the mobile agents along their trajectories and dynamically estimate the spatial concentration of different odor fields. The data assimilation process is made centrally by a PC that polls periodically each robot through a RF network in order to get the data gathered during the previous acquisition period. The estimation of odor fields is made in two steps: first each agent estimates the odor mixture and concentration by means of a neural network-based regression algorithm that converts values from gas sensor space to the corresponding odor space. Then the sensed data is assimilated into an advection-diffusion model by means of a reduced order Kalman filter. In the current implementation the central controller, responsible for the maps estimation, specifies to each agent their target area to explore. The proposed architecture was validated with a set of experiments that demonstrated its ability to estimate and capture the dynamics of overlapping odor fields. This work can easily be adapted to city buses or other local transportation systems in order to monitor the pollution or quickly detect hazardous chemicals inside cities.

  • Finding Odours Across Large Search Spaces: A Particle Swarm-Based Approach
    Climbing and Walking Robots, 2005
    Co-Authors: Lino Marques, A T De Almeida
    Abstract:

    This paper proposes an evolutionary-based search algorithm to find odour sources with robot communities across large search spaces. The characteristics of outdoor odour plumes and the main problems in detecting and finding them in real environments are described. An artificial olfaction system designed to carry out olfaction-based mobile robot experiments in realistic conditions is shown. This olfaction system is composed by intelligent gas sensing nostrils and a directional Thermal Anemometer. The searching algorithm proposed is inspired in the particle swarm optimization (PSO) method. This algorithm allows coordinating the movements of multiple robots searching for odour sources across large search spaces. The paper describes the algorithm and compares its performance against other searching strategies.

  • Environmental monitoring with mobile robots
    2005 IEEE RSJ International Conference on Intelligent Robots and Systems, 2005
    Co-Authors: L. Marques, A. Martins, A T De Almeida
    Abstract:

    This paper describes an architecture for estimating environmental odor maps and presents experimental results obtained using that architecture with five mobile robots inside a large laboratory with two odor sources and forced ventilation. The mobile sensing agents employed in the experiments have self localization capabilities and carry an electronic nose and a Thermal Anemometer. The proposed architecture allows integrating sparse olfaction data gathered by the mobile agents along their trajectories and dynamically estimate the spatial concentration of different odor fields. The data assimilation process is made centrally by a PC that polls periodically each robot through a RF network in order to get the data gathered during the previous acquisition period. The estimation of odor fields is made in two steps: first each agent estimates the odor mixture and concentration by means of a neural network-based regression algorithm that converts values from gas sensor space to the corresponding odor space. Then the sensed data is assimilated into an advection-diffusion model by means of a reduced order Kalman filter. In the current implementation the central controller, responsible for the maps estimation, specifies to each agent their target area to explore. The proposed architecture was validated with a set of experiments that demonstrated its ability to estimate and capture the dynamics of overlapping odor fields. This work can easily be adapted to city buses or other local transportation systems in order to monitor the pollution or quickly detect hazardous chemicals inside cities.

Debashis Maji - One of the best experts on this subject based on the ideXlab platform.

  • Simulation and feasibility study of flow sensor on flexible polymer for healthcare application
    IEEE Transactions on Biomedical Engineering, 2013
    Co-Authors: Debashis Maji, Soumen Das
    Abstract:

    Development of micro-fabrication technology, along with an ever increasing demand for reliable, low cost clinical health care has led to the realization of various BioMEMS devices. Present study aims at developing a flexible flow sensor on polymer substrate to monitor real-time blood flow and determine plague formation satisfying sensitivity, biocompatibility, and reliability requirements. Transient simulation of temperature and velocity profile of the Thermal Anemometer based sensor wrapped around the catheter has been studied. Initial fabrication of the sensor over PDMS polymer along with Thermal coefficient of resistance (TCR) measurement and flow sensing over straight heater has also been performed. The simulation and fabrication works shows promising results towards successful development of a flow sensor for effective healthcare delivery.

  • Simulation and Feasibility Study of Flow Sensor on Flexible Polymer for Healthcare Application
    IEEE Transactions on Biomedical Engineering, 2013
    Co-Authors: Debashis Maji
    Abstract:

    Development of microfabrication technology, along with an ever-increasing demand for reliable, low-cost clinical healthcare has led to the realization of various BioMEMS devices. Present study aims at developing a flexible flow sensor on polymer substrate to monitor real-time blood flow and determine plague formation satisfying sensitivity, biocompatibility, and reliability requirements. Transient simulation of temperature and velocity profile of the Thermal-Anemometer-based sensor wrapped around the catheter has been studied. Initial fabrication of the sensor over polydimethylsiloxane (PDMS) polymer along with Thermal coefficient of resistance (TCR) measurement and flow sensing over straight heater has also been performed. The simulation and fabrication works show promising results toward successful development of a flow sensor for effective healthcare delivery.

Alfiero Leoni - One of the best experts on this subject based on the ideXlab platform.

  • Sensors - A Multisensorial Thermal Anemometer System
    Sensors, 2017
    Co-Authors: L Pantoli, Romina Paolucci, Mirco Muttillo, P Fusacchia, Alfiero Leoni
    Abstract:

    This work deals on the design of a multisensorial Anemometer able to provide an accurate measurement of both wind speed and direction. The system is based on Thermal anemometry that is, probably, the preferable way to measure instantaneous wind velocity in any weather condition and surrounding. The application here proposed is based on a commercial flow probe, the IST FS5 that shows a robust design without moving parts, small dimensions and is suitable to operate up to 150 °C and a wind speed of 100 m/s. In addition, the sensor is organized as a pattern of probes. In this way, being the analysis based on differential measurements, analyzing the signal provided by each sensor is possible to perform an accurate evaluation of both the wind speed and direction. A microcontroller realizes the data management and wind flow identification process.

  • a multisensorial Thermal Anemometer system
    Sensors, 2016
    Co-Authors: L Pantoli, Romina Paolucci, Mirco Muttillo, P Fusacchia, Alfiero Leoni
    Abstract:

    This work deals on the design of a multisensorial Anemometer able to provide an accurate measurement of both wind speed and direction. The system is based on Thermal anemometry that is, probably, the preferable way to measure instantaneous wind velocity in any weather condition and surrounding. The application here proposed is based on a commercial flow probe, the IST FS5 that shows a robust design without moving parts, small dimensions and is suitable to operate up to 150 °C and a wind speed of 100 m/s. In addition, the sensor is organized as a pattern of probes. In this way, being the analysis based on differential measurements, analyzing the signal provided by each sensor is possible to perform an accurate evaluation of both the wind speed and direction. A microcontroller realizes the data management and wind flow identification process.

Qingan Huang - One of the best experts on this subject based on the ideXlab platform.

  • Wide span Thermal wind sensor system with dual chips
    2013 IEEE SENSORS, 2013
    Co-Authors: Lin Zhou, Sheng-qi Cheng, Tian-yu Xiang, Bei Cheng, Qingan Huang
    Abstract:

    A novel Thermal wind sensor system based on dual chips was presented in this paper. One chip is Thermal Anemometer, which operates in Constant Temperature Difference (CTD) mode, another is calorimetric wind sensor, which operates in Constant Power (CP) mode. Both chips are designed to work at the same time. In the low wind speed (from 0 to 10m/s for example), the CP mode chip can detect accurate wind velocity and direction with less temperature drift, which is used as a reference for calculating the offset voltage of the CTD mode chip caused by the variation of ambient temperature; meanwhile the data are also as the output of the system. So compared with single chip wind sensors, the dual chips wind system can detect both low and high wind speed with higher accuracy and less temperature drift. The testing results indicate that the accuracy of low wind speed under 10m/s is ±0.3m/s and that of high speed from 10m/s to 40m/s is ±0.6m/s, and the measurement span is above 40m/s. In this system, dual chips are designed to operate in two different modes and their outputs are detected by a Micro Controller Unit (MCU).

  • A system-level model for a silicon Thermal flow sensor
    Microsystem Technologies-micro-and Nanosystems-information Storage and Processing Systems, 2008
    Co-Authors: Guangping Shen, Qingan Huang
    Abstract:

    A system-level model with lumped parameters for a Thermal flow sensor is presented. The model is built with 13 circuit cells consisting of Thermal resistors and Thermal capacitors in SPICE. The circuit cell originates from the heat conduction equation using the Finite Differential Method, including the 2-D Thermal conduction cell, the convection cell, and the Thermal capacity in the chip. Based on the Thermal model of the flow sensor, the 2-D temperature distribution of the chip can be calculated with SPICE in both the constant power mode (CP) and constant temperature difference mode (CTD). As an example, the system level model of the Thermal Anemometer in the CTD mode was established in PSPICE. Wind tunnel test was carried out to verify the system model, and show a reasonable agreement with the simulation results, with an error less than 8%.

  • SPICE Model with Lumped Circuits for A Thermal Flow Sensor
    2006 5th IEEE Conference on Sensors, 2006
    Co-Authors: Guangping Shen, Qingan Huang
    Abstract:

    A novel lumped parameter SPICE model for a Thermal flow sensor is presented. The model is constructed by 13 circuit cells consisting of Thermal resistors and Thermal capacitors. The circuit cell originates from the heat conduction equation using the Finite Differential Method, including the 2-D Thermal conduction cell, the convection cell and the Thermal capacity in the chip. Based on the Thermal model of the flow sensor, the 2-D temperature distribution of the chip can be calculated with SPICE in both the constant power mode (CP) and constant temperature difference mode (CTD). As an example, the Thermal Anemometer in CTD mode is measured in the wind tunnel to verify the model. The simulation results show a reasonable agreement with the experiments, with an error less than 8%. The proposed model is valuable to design the Thermal flow sensor with system-level simulation.

  • novel micromachined Thermal Anemometer based on lateral polysilicon diode flow sensor
    Micromachining and Microfabrication Process Technology and Devices, 2001
    Co-Authors: Qingan Huang, Zhaoyong Zhang
    Abstract:

    A new micromachined Thermal Anemometer based on laterally polysilicon diode (LPD) temperature-sensing elements is developed in the paper. The LPD was fabricated with CMOS compatible process and its temperature-sensing characterization is also investigated. The measured results show the forward current increases with temperature near linearly. The temperature coefficient is about 1.8mV/K, which is close to that of monocrystalline silicon diode. A Anemometer with a ring-like polysilicon heater and 8 LPD temperature-sensing elements were fabricated and characterized, air flow up to 120 cm 3 /s was measured and more than 8 directions of wind can be detected.

Soumen Das - One of the best experts on this subject based on the ideXlab platform.

  • Simulation and feasibility study of flow sensor on flexible polymer for healthcare application
    IEEE Transactions on Biomedical Engineering, 2013
    Co-Authors: Debashis Maji, Soumen Das
    Abstract:

    Development of micro-fabrication technology, along with an ever increasing demand for reliable, low cost clinical health care has led to the realization of various BioMEMS devices. Present study aims at developing a flexible flow sensor on polymer substrate to monitor real-time blood flow and determine plague formation satisfying sensitivity, biocompatibility, and reliability requirements. Transient simulation of temperature and velocity profile of the Thermal Anemometer based sensor wrapped around the catheter has been studied. Initial fabrication of the sensor over PDMS polymer along with Thermal coefficient of resistance (TCR) measurement and flow sensing over straight heater has also been performed. The simulation and fabrication works shows promising results towards successful development of a flow sensor for effective healthcare delivery.